TDA8385 Datasheet, PDF (10/21 Pages) NXP Semiconductors – Control circuit for a Self-Oscillating Power Supply SOPS

Philips Semiconductors
Control circuit for a Self-Oscillating
Power Supply (SOPS)
Preliminary specification
TDA8385
Stand-by circuit (Block IX)
During stand-by operation the voltage V_sb is supplied from the SOPS via thyristor TH1 (see Fig.16). In the stand-by state,
SOPS operates in a burst mode. When the voltage on pin 10 exceeds 2.5 V the LED driver is permanently activated. The
LED driver is released again if the voltage is below 2 V (see Fig.11).
handbook, full pagewidth
Vsb
(V)
2.5 V
2V
0
output sub-section 25
0
I _LED
(mA)
0
t
t
5 mA
t
MCD410
Fig.11 Stand-by operation; burst mode.
March 1994
11